fix typo in utils.less

Author: aminya

static/core-ui/utils.less

@@ -7,4 +7,4 @@
 @contain_but_paint: layout size style;
 @contain_but_layout_size: paint style;
 @contain_but_layout_paint: size style;
-@containt_but_size_paint: layout style;
+@contain_but_size_paint: layout style;